Concrete is a mixture of cementitious material, aggregates and water. Generally, aggregates are considered to be inert fillers, making up 60 to 80 percent of the volume and 70 to 85 percent of the weight of concrete. However, a closer look reveals that aggregate plays a primary role in influencing the properties of both fresh and hardened concrete. Changes in gradation, maximum size, unit weight, and moisture content can all alter the character and performance of the concrete mix.
Cement is similar to aggregate in that it contains sand, one of the most commonly used aggregates. Cement is slightly thicker than aggregate because it is finely ground rock, usually limestone or shale. Strength performance is the most important property of structural concrete from an engineering point of view. The relationship between concrete composition and mechanical properties has been a topic of research for some time.
Aggregate has an earthy appearance that varies in color depending on the minerals it contains. For example, smooth round aggregates create a smooth final product, while angular crushed rocks produce jagged edges and surface texture. Digital imaging methods have been used to efficiently and rapidly analyze aggregate characteristics such as shape index, size distribution, surface texture, etc. Studies on determining the textural properties of aggregates by image analysis were performed on test specimens of hardened concrete with a cure time of 28 days.
Aggregates are either natural resources such as crushed stone, gravel or sand, or manufactured products such as recycled concrete and fly ash. The use of aggregates for construction purposes is much more sustainable than the use of cement or concrete. In this study, the effects of the textural properties of aggregates on the properties of hardened concrete were investigated. The ratio between coarse-grained and fine aggregates will vary depending on the unique characteristics of each aggregate, the method of placement and the desired finish.
Mohammed and Mahmood used the aggregates they produced from brick fractures as coarse-grained aggregates in the concrete composition and investigated the relationship between coarse-grained aggregate and ultrasonic transition rate using image analysis. The aggregates were tested for specific gravity, absorbency, unit weight, and abrasion resistance. Many studies have addressed recycling rubber tires as a replacement material for fine or coarse-grained aggregates used in concrete mixes. This is a summary of the most important factors to consider when selecting and dosing concrete aggregate. In addition to strength and durability properties, the textural properties of the aggregate can also affect the properties of hardened concrete.
The strength and durability properties of the aggregate can affect both fresh and hardened concrete.